Semi-automatic telephone system.



H. 1. HERINK SEMI-AUTOMATIC TELEPHONE SYSTEM1` Y. APPL| C'AT10N FILED4 MAR. 9. |911. v 1,250,583, Patented Dee. 18, M7;

3 SHEETS-SHEET n.1. HERINK. SEMI-AUTOMATICTELEPHONE SYSTEM.

APPLICATION FILED MAR. 9. 1917.

f Patented me. 18, 1917.

3 SHEETS-SHEET 2- l H. J. HERINK. SEMI-AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED MAR. 9. l9l7.

Patented Dee. y18,1917'.

L- l 3 SHEETS-SHEET 3.

mman STATES rarnifrrI onirica.

HNRY- AJAMES HERINic, oF -Lo'1\mo'1\;r,` ENGLA1\T-n-ASSIGNOR yTo THE RELAY VAUToiVLA'lIc TELEPHONE COMPANY, YLINEE-ED,elLONDON, ENGLAND-` Y.

sErfILA'T'oiVrAric TELEPHONE SYSTEM.

Specification of LettersrPatent. l I

wauw-hammaycaamf l Y Be itk-nbwnthat' LHENRY'JAMS HERINK, a subject of the Kingof 'Great Britainyaiid rsident oM'arconi House; Stra-nd;4 London,

Englandhav'ei invented anew and useful Improvement iii-jSeiniAutomatic Telephone Systems;Y of? which the 'following isf a' speci` iication. This invention relates toY semi-automatic telephone `systems Whichthere is a satellite"exchang connected withv a m'anualcen tr'al eiichange; This applicationl claims more* particularly l thel meteringE and associated arrangements; 4certain 'other features being claimed under myV applica-tion* No'. 130551. Y Y

The object of V'the invention" is so to' ar@ range' the-` `'circuits' a-nd'ithe apparatus ``at ythe satellite 1 that lWhile "acalling subscriber can clear' until-"the operator'h'as insertedhi' pluginy answer-'to Ihis cali,V so soon -as she has done so th'e circuits are-under her con# trolV s' that fshe can actuate the 'subscribers meter levenV after he' has replaced his ref ceiver', which 'she does 'bysen'cling alterna-ting :current over' the trunk; Yto the satellite. My invention'is"illustrated by the'a'ccn'i-y panyiig drawingsof which Y Figure '1 shows a'circuit; associated Withdouble pre-'selectorfli-ne'-inder 'relay switches' as described in'fBriti'sli-Patent No.102330.'-

Al subscribersfline has therebjf'access to a plurality 'of tWdWire-trunks to "an 'A' posi- Fig. 2 shows myinventionjapplied ta relay l's ystemfof the type described in Bri'tf ish Patent No. 9840 of 1915iV and United StatesPatent Serial No. 832471,; With certain 'lnodiiications` Fig." Svshow's the use Vof repeater'siinthe transmission circuits and other features;

At the satellite (Fig. 1) Iemploy tWo supervisory Arelays 'SlR and SQRQtWo guardi ing relays G1R and GR?,` v a` super.fisory switching VVrelay SSR; a flnargina'l 'changeover relayMCR and a nieterifngfrela'y SMR adapted lto respond to` alternating' current7 While iat -the A' position'von' the manual board I have line relay rL1B", a -"cuto'ff relay COlR, a metering recording and metering vswitching relay hejoperation oftheci'rcuit 1s asfollows The callingl"subscribe"j on` -l-i-ftirg A'his re-y lamp CD'gloWs. N ow ifthe calling: sub

vscriber clears before "the"l operator answers,

. SIR denergi'zes, then SSR: which opens 'cir cu'it Vt of G1R: before the latter denergizes,

GRienergiZesfover circuit 6a. i

When G1R does'releasepthe circuits 0 and l'aie 'opened `during the timebetween the fallinglof of G1R and GR'. This 4time is"suiicientto-release the line `finder.

Assuming? that thefca'lliiig subscriber does not clear befovrethe'operatoranswers,L the insertion ofthe plug energi'zes CClR Vover circuit 6 andcuts out L1B and'circuit;

MCR new energizes 'overfcircuit 7. V

, GR enefrg'izes over circuit 8f andlnainta'ifns itself-over"circuit` 9 which is estab'-` lished'b'efore Acircuit' 7 'is broken. Circuit 1 is new retained'over G1R and `MCR denergi-zesbythe opening'of circuit 7 at GR." -S4R and -SQR areV energized via circuit '10; Lamp 4SL is vshunted outby circuit 6. f SQR energizingvconnects "circuits 11 andV "12 toearth and thus controls GR and G1R.

Thus it is seen that the release' of 'a line finder by retaining'circuit Ois controlled from?, S21?,l Whichfis maintained over 'thef answering plug circuit. When Vthe 'operator inserts "a plug; thev control of the circuit thus passesl 'from' the calling subscriber to the operator. The calling subscriber is able, 'by moving the switch-hook and openin I'and closing circuit 2,-V to cause'SlR'and SR' co'n's'ecutivelyr vto energize and" deener# giz'e',r thus divertingA circuit 10 to 10al Via resistance This resistance .is such that SLR Willr also 'denergize and `'rei'ne1c5.;ize, but'y SQR is of such a resistance that it will continue'ito4 be maintained energized. Thus cir-y cuit 6l is'alternatively openedand closed to flash rlamp YSL.

The'operatorjisfnowable to obtain the' number ir'eqiiire'd by' the* calling" subscriber J and completes the connection in a well known manner. At the termination of conversation, the calling subscriber will open circuit 2 and cause SL toglow as previously described.

The call, if eective, will bemetered. 1f ineffective, or on no-fee service, the operator will simply withdraw the plug. 1n any case the clearing of the circuit is vunaffected by metering.

,1f the operator depresses meter key K, circuit 13 energizes MSR which by switching in its low resistance winding energizes the operators meter in a well known manner. MSR` causes an alternatingcurrent, superimposed upon a continuous current, to pass over circuits 14 and 10a. The continuous cur.- rent maintains S2R but the alternating cur rent energizes SMR which maintains itself over 15. Circuit 16 is now completed to short-circuit resistance RG and increase the current in the subscribers meter so that Ait is energized. The operator now withdraws the plug. MSR, COiR denergize, then S2R. T he latter causes circuits 11 and .12 to beopened. G1R falls off first and then GR. The interval `of time is sufficient to release the line finder. as previously described.

Fig. 2 Shows a subscribers line equipment connected at CRl, CR2, in a relay system of the type described in British Patent No. 9840 of 1914 and United States Patent Serial No. 832471, extendedto a transmission circuit according toa modication of my invention According-tolig. 1, the operator can only cause the meter to register after the subscriber has replaced his receiver. The subscriber can therefore hold the trunk against the wishes of the operator. According to Fig. 2, the operator controls the trunk absolutely and can register a call whether the receiver is replaced or not. The trunk is shown plug-ended, and when this plug has been inserted into the jack of the wanted line the operator .has full control, and when the plug is withdrawn after conversation the connection is released back to the line and cut-off relay independent of any action of the caller. It is to be understood `that this feature is applicable to the system of Fig.V

1 or to any other system, and the transmission circuit of Fig. 1 has also such wideapplication. y y e rThe operation of Fig. 2 is as followsr# The subscriber lifts the receiver and circuit 1 is completed to energize the line relay LR. The line is then connected tol an idle trunk in the manner described in British Patent No. 9840 of 1914 and United States Patent Serial No. 832471. Relay SR energizes over circuit 2; relay SSR energizes over circuit 3; relay G1R energizes over circuit 4. Relay COR, energizing over cire cuit 5, cuts off LR and energizes relay AR over circuit V18. Circuit 6 is completed by SSR, and relay LR2 (but not relay MCR) energizes completing circuit 7 to glow lamp S3L. -Let it be assumed thatv the subscriber *now replaces his receiver. Circuit 2 is broken, and SR and SSR deenergize, causing cii'cuits4`and 6 to open, thus releasing the trunk. Assuming that the calling subscriber does not clear at this stage and the operator answers in a well known manner` by operating key K1, she obtains the number required. She then inserts the callingplug into the required line jack when relay SCR operates and lamp VS4L glows in circuit 8'. The subscriber may be rung manually or by automatic devices well known in the art. y

The operation of SCRearths the AY line of the trunk and Vcauses MCR to operate over circuit 9. GR now energizes incircuilI 10. S2R energizes in circuit l1 and G1R is maintained overcircuit 12. GR is maintained over circuit 13 which is established before circuit 9 is broken. MMR energizes overcircuit 13a. The calling subscriber may flash the operator as described for Fig. 1 if he so desire. Relays SR and SSR energize and denergize and make and break circuit 11, so that S3R is denergized andV energized to cause lamp SSL to glow intermittently. The operator, assuming the call to have been effective, will depress K2 to energize the operators meter SMB and relay MSR over circuit 14. The latter relay causes SMR to energize by alternating current over circuit 15. SMR holds itself over circuit 16 and cuts out MMR but itself remains energized sufliciently long, owing to the slow release of MMR, Vto complete circuit 17 to short-circuit the resistance in earth of circuit 5, and the increased current causes subscribers meter SM to en-Y ergize. The calling subscriber may or may not'have replaced his receiver. Y v

In the latter case, the operatorv by withdrawing the calling plug causes SCR to deenergize, thus opening circuitll and causf ing S2R to denergize. Circuit 12 being opened, G1R denergizes and opens circuit 5 to denergize CRl and CR2. GR also de.-

energizes, but being slow to release does not prevent the breaking down ofthe connection. .CCR denergizes but relay ARl (see United States Patent Serial No. 101769) is maintained energized over circuit 18, thus giving the calling subscriber the busy-tone.

(This facility can also be utilized when the wanted subscriber is busy, the operator thenk momentarily putting the sleeve of the callingftrunk plug to earth in any Well `known manner.k This will give the calling subscriber busy-tone and release the trunk). Y

.If the calling subscriber replaces the re.- ceiver before the withdrawalof the plug, the operator will meter as already described.

Circuit 2 being open at the switch-hook, SR,

SSR denergize, then SSR because the shortcircult of resistance R in circuit l1v is re- .party has replacedfthe receiver.

muted byu-SSR. ..Circutatlt-bengithencompleted, lamp SSL glows. When thealld Sllbscriber .replaces'his receiver, ,SflRdeneragzingrcmones the StL vglows; v

ig. L@shows .my nuentonpuscd' with .re-`

shunt Raise thatlamp peatcr coilftransmissfarr.` lThis arrangement release .the rconnection unless the .calling 'The operation of `the circuityis .as-followsf:"- Y i f I'Vhen the receivery is lifted to call, a subscribersline is extended toy aftrunk in any known manner. Circuits .0and 1,.:Figs. '1 and 2, are completed, the cut-ott relay energizedr and thellinerelay disconnected, as before described. l

`Relay SR' is nowfenergizedover-circuitQ, and circuit 3 being completed SSR energizes. Circuit 4 being completed G1R energizes and adds to circuits and 1 by paths 0a and 1a respectively. Circuit 5 is also completed by SSR and LlR energzes but not MCR. LlR completes' circuit 6 and lamp SL glows. Y

If the caller clears at this stage, circuit 2 Opens and causes S5R to denergize. GR energizes over circuit 7 and holding itself over circuit 8 releases its connection as described for Fig. 1.

INhen the operator answers before the subscriber clears, circuit 8a, completed over the plug third conductor, energizes COlR which cuts o' relay L1B so that it denergizes and lamp SL ceases to glo-w.

MCR is energized over circuit 9, as de- I scribedfor Fig. 1. This relay energizes GR over circuit 1() and the later retains over circuit 8 lwhich is established before circuit 9 is broken. Circuit 11 is now established over the plug, as in Fig. 1; SQR energizes and switching in its low resistance winding, 11a causes the supervisory relay of the operators cord circuit to energize', asin Fig. 1. The caller may now' flash the operator as before described. SR and SSR open and close the low winding of SQR. The caller replacing the receiver permanently glows the supervisory lamp in a similar manner.

The operator then depresses the meter key (Figjl) and energizes MSR over 8", causing SMlR to energize over circuit 14. The latter relayT retains over circuit 14E a relay MI-IR having been energized via circuit 13.V

MHR being slow to release circuit 15 is established a sufiicient time to short-circuit resistance RO, causing the meter of the calling subscribers line to operate as in Fig. 2.

It is to be noted that G1R is retained energzsdover :circuiti-'12', and fthatriS'SgR is de- .ener-gized bypcrcut heingaopen .at 55B.

Thereforeiwhen.theioperator wthdraws` the plus., SQIR denerlgizes end .opens circuit 12 .Soft-hatt. :isfvclener-gized.. The `.retaining circuits'. O I11 aren opone,d fluetweenY ther-deenergizations .aGrLR: and GR, asufIiGient length-. ofltmeto release the connection.

What/f1 -v 1. In a semi-automatic telephonelsystenl .using two-wire;trunkspthe;combination. of a .Subscribers-meter controllrelay .adaptedeto Respond. ...to alternati-ng .current ,only means whereby, after 1a. calling 'linejihas been ,extended to an .operator-sz connecting` equip@ ment, alternating lJcurrent; maybe applied to )the control `relay to effect registration. y

' .2. lIn a.semi'fautomatic telephoneA system .using two-wire trunks, .f the -,.combinationVv of a ,su-bsciibers1-meter .contro-l, relay. adapted :tp .respond to alternating current only, means wfor enabling a caller to return all apparatus to normal beforethe operatoi;replies,.means forpreventing him from doing so thereafter and means for enabling the operator when once the answering plug has been vinserted to apply alternating current to the control relay and to return apparatus to normal.

3. In a semi-automatic telephone vsystem using twoewire trunks, the combination of a meter control relay adapted to respond to alternating current only, a condenser, a double wound relay operatively connected across a trunk at a satellite exchange, means whereby the meter control. relay and the condenser are connected in parallel with the double wound relay, means for retaining the last mentioned relay energized by continuous current and a meter-key adapted to energize the meter control relay by alternating current.

f1. In a semi-automatic telephone system using two-wire trunks, the combination of a repeater, a condenser connected between two windings of the repeater, a relay shunting the condenser, a meter control relay and aV second condenser both connected in parallel with the first' mentioned relay, means for energizingthe first relay by continuous current and a meter key adapted to energize the meter control relay by alternating current.

5. In a semi-automatic telephone lsystem using two-wire trunks, the combination of a subscribers line, a meter control relay associated therewith and adapted to'respond to alternating current only, a relay operatively connected to the line and adapted to extend the line to a trunk, means actuated by the answering of an operator for cutting'o the second relay from the line andmeans for applying alternating current to the meter control relay. l

6. In a semi-automatic telephone system using two-wire trunks,`the combination of to alternating current only, a marginal relay operatively connected to lthe line and adapted to extend the line to a trunk without itself operating, means actuated by the answering 'of an operator for operating the marginal relay and for cutting it oil from the line and means for applying alternating current to the meter control relay.

7 In a semi-automatic telephone system .using two-wire trunks, the combination of a subscribers line, a meter control relay -associated therewith and adapted to respond to altenating current only, a relay operatively connected to oneline branch of the subscribers line, means actuated by the answering` of an operator for energizing the second relay over the line, means whereby the operationA of the second relay enables the operator to release and means for applying by the' operator, means whereby the other of such slow release relays is controlled by the answering of the operator, means for transi'erring release from the first to the second of such relays and means for applying alternating current to the meter control relay.

In testimony that l claim the oregoing as my invention, I have Signed myv name this 14th day of February, 1917.

HENRY JAMES HERINK.

v Copies o this patent may be obtained for fivey cents each, by addressing the Commissioner of Patents, Washington, 13,0. n 

